Indexing mechanism for drill presses or the like



3, 1955 J. c. BENDER 2,715,844

INDEXING MECHANISM FOR DRILL PRESSES OR THE LIKE Filed July 16, 1951 4 Sheets-Sheet l INVENTOR. JOHN 0. BE N05 1? ATTORNEY mm m% R 9% mm a W m? Haul W4 Q? Q n 0@ I R Rh ah INVENTOR.

ATTORNEY Aug. 23, 1955 J. c. BENDER INDEXING MECHANISM FOR DRILL PRESSES OR THE LIKE Filed July 16, 1951 4 Sheets-Sheet 2 JOHN 0. BE NDE f? I OM 4 Aug. 23, 1955 J. c. BENDER 2,715,844

INDEXING MECHANISM FOR DRILL PRESSES OR THE LIKE Filed July 16, 1951 4 Sheets-Sheet 5 wil NW1... 7 mlln h.

IN V EN TOR. JOHN 6. BE NOE R ATTORNEY INDEXING MECHANISM FOR DRILL PRESSES OR THE LIKE Filed July 16, 1951 Aug. 23, 1955 J. c. BENDER 4 Sheets-Sheet 4 IN V EN TOR. JOHN C. BE/VDER ATTORNEY United States Patent INDEXING MECHANISM FOR DRILL PRESSES OR THE LIKE John C. Bender, 'Hartville, Ohio Application July 16, 1951, Serial No. 236,982

6 Claims. (Cl. 77-5 This invention relates to drill presses, and in particular relates to a mechanism for automaticallyindexing work on drill presses or the like for performing a succession of operations on the work.

There are on the market at the present time a number of popular types of drill presses manually operable to move a revolving drill toward work mounted on a table. These presses are popular in the trade because they are economical to purchase and are otherwise satisfactory for ordinary drilling operations.

A general object of this invention is to provide a unitary indexing mechanism which is easily mounted on a standard drill press of the type described, and by which the drill press is readily and economically adaptable automatically to perform a succession of operations on work, without requiring substantial modification of the original elements of the press.

Another object of the invention is to provide an indexing mechanism of the character described which is readily adjustable for installation on drill or like presses of the type described within a substantial range .of sizes and proportions.

Another object of the invention is to provide in a machine of the character described an improved mechanism which is easily adjustable to perform one operation on a succession .of pieces of work or to perform a succession of equally or unequally spaced operations on the same piece of work.

These and other objects of the invention will be manifest from the following brief description and the accompanying drawings.

Of the accompanying drawings:

Figure 1 is a side elevation, partly broken away, of a common type of drill press having incorporated therein a unitary indexing mechanism in accordance with the invention,

Figure 2 is a horizontal cross-section taken substantially on the line 22 of Figure 1, illustrating in particular a power-output unit of the indexing mechanism, mounted on the usual upright of the press.

Figure 3 is a cross-section through a manually operable clutch, taken substantially on the line 33 of Figure 2.

Figure 4 is a horizontal cross-section taken substantially on the line 44 of Figure 1; illustrating a workholding unit of the indexing mechanism, mounted on the usual work-supporting table of the press.

Figure 5 is an enlarged cross-section, taken substantially on the line 5-5 of Figure 4.

Figure 6 is a fragmentary rear view of the power-output unit, as viewed substantially on the line 66 of Figure 2.

Figure 7 is an enlarged perspective view of a trip used for indexing the stopped positions of the work-holder.

Referring particularly to Figures 1 to 6 there is illustrated an automatically operable indexing mechanism 10, incorporated in a drill press 11 of well-known type. The indexing mechanism may comprise two main units,

Patented Aug. 23, 1955 ICC namely a work-holder unit W and a power-output unit P, both to be described later.

Such presses usually comprise a standard including a base 12, a cylindrical upright 13 thereon, a head or casing 14 fixed on the upper end of the upright to overhang a horizontal work-supporting table 15, carried by an arm 16 which is releasably clamped to the upright to be vertically and swingably adjustabie thereon. In head 14 is a spindle or tool-holder l7, vertically reciprocable by gear means 18, shown in chain-dotted lines in Figure 2, and including a shaft 19, journaled in the head, on an outward extension 20 of which is keyed the usual hand wheel 21 for manually lowering the tool-holder 17 to move a drill 22 or other tool in a chuck on the lower end of the same toward work on the table. Adjustable stop means 24 is provided on the tool-holder and head for limiting upward return movement of the tool-holder, as urged by spring means 25. The tool-holder is rotated by suitable power means including an electric motor 26.

As best shown in Figures 4 and 5, the work-holder unit W may include a plate 29 which is bolted at 30, 30 to the table 15, and a hollow work-holder 31, the same being composed of a bottom part 32 rotatably supported on the plate 29, as by means of a bolt 33, and a top part 34 non-rotatably attached to said bottom part, as by screws 35, 35. Arranged across the top face of top part 34 are angularly disposed T-slots 36 and 37, slidably adjustable to receive T-heads of bolts 38 of clamping lugs 39 by which drilling fixture 4% for example, containing work 41 to be drilled, is releasably attached to the top of the work-holder. The work-holder is rotated in a manner to 'be described by a pinion 43, in a block 44 mounted on plate 29 at one side of the work-holder, meshing with a large gear 45 integral with bottom part 32 of the workholder, the pinion 43 being rotatable by an intermittently rotated shaft extension 46 journalled in a flange 47 on bracket 48 of the power-output unit (see Figures 1 and 2), through a link 49 swivelly connected at its lower end to an upward extension 50 of the pinion and swivelly connected at its upper end to a rod 51 journalled in a flange 52 on said bracket 48 at right angles to flange 47, said rod '51 and said shaft extension 46 having thereon meshing bevel gears 53 and 54.

Shaft extension 46 (Figures 1 and 2) is driven for predetermined periods by an intermittently operated clutch member 55 on a constantly driven shaft 56 journalled in the bracket 48 in alignment with said shaft extension 46, the clutch member 55 having a toothed portion 57 complementally engageable with a toothed member 58 fixed on the extension 46. For constantly driving the shaft 56 the same may be connected, through a normally closed, hand-operated clutch mechanism 7i, a shaft extension 57, a worm gear 58 meshing with a worm 59 on shaft 60, and a V-belt extended between variable speed pulleys 61 and 62 on the worm shaft 66 and an output shaft 63 on motor 26.

Referring again to Figures 4 and 5, the work-holder unit W also includes means for controlling rotation of work-holder 31, as for drilling arcuately spaced holes in work 40 mounted in the fixture 39. Accordingly, a series of trips 64 extend horizontally from the outer periphery of the upper work-holder part 34, to be engageable with an upstanding finger 65 on a catch 66 constituting a pivoted arm which is normally held against a stop by a spring 67, the stop in the present instance being a projecting portion of the pinion extension 50. In this stop position of the catch 66 the finger 65 supports a detent 68, pivoted at 79 to the block 44, to have a downwardly extending bifurcated or notched end 70 positioned above the path of the trips 64. The detent 68 tends to be urged downwardly by a compression spring 72 engaged between an extension 73 thereof on opposite side of the pivot 69 and an attachment 74 on the block.

A'rod or driving connection 75 is swivelly connected at its lower end to said extension 73 (see Figure 1) and has its upper end received through an aperture 76 in one arm 77 of a bell-crank 78 pivoted at 79 on the bracket 48. The other arm 80 of the bell-crank is held in engagement with a roller 81 on the free end of a slide-bar 82, horizontally slidable through spaced lugs 83 and 84 on the fixed bracket 48, the slide bar being attached adjacent its free end to the movable clutch member 55. A collar 85 slidably adjustably fixed on'the upper end of rod 75 supports the bell-crank arm 77, so that when a trip 64 on the rotating work-holder yieldingly engages the catch 66 to release the finger 65 thereof from support of detent 68, the latter is yieldingly urged downwardly to engage the bifurcated end 70 of the detent over the. respective trip to index or grip the work-holder in a stopped position for a drilling operation to be described. Rotation of the work-holder is stopped at the instant this gripping action takes place by resulting upward movement of rod 75 pivoting the bell-crank in counterclockwise direction to move the slide-bar 82 to the left (see Figures 1 and 2), and thereby to disengage the clutch 55.

The clutch member 55 remains disengaged and the work-holder 31 remains stationary for a period long enough to permit a drilling operation on the work 41. Accordingly, a portion of the normally constantly driven shaft 56 constitutes a worm 87 in relatively slow driving connection with a worm gear 88 keyed on a cross-shaft 89 journalled in a lateral extension 90 of the bracket 48, cross-shaft 89 having keyed thereon a cam 91 intermittently engageable with a grooved portion 92 on the slide-bar 82 to reengage the clutch member 55, after the drilling operation has been performed on the work and again to rotate the work-holder in the manner described above, until it is similarly stopped by the next succeeding trip 64 releasing the detent 68.

At the. opposite end of cross-shaft 89 from the cam 91 is another cam 93 in engagement with a roller 94 on an arm or quadrant 95 pivoted on the bracket 48, an arcuate toothed portion 96 on the free end of the quadrant meshing with a pinion 97 suitably fixed on the tool-holder operating shaft 20 (see Figures 2 and 6). The cam 93 and associated parts are designed to urge the tool-holder be clamped together on the upright, as by means of set screws 101, 101. The bracket may be supplied to a purchaser of the indexing mechanism with the cylindrical bore 102 therethrough relatively smaller than normally required so that it may be readily turned or machined to requisite diameter to fit a particular upright 13, 'uprights on drill presses on the market being of varying diameters.

As best shown in Figures 6 and 7, the trips 64 are adapted to be easily adjusted on the work-holder 31 to drill any number of holes either equally or unequally spaced apart. Accordingly, each trip 64 may comprise a stem part 103 on which is threaded a nut 104. Fixed on one end of said stem part may be plate 105 of relatively narrow width to permit ready reception thereof through the relatively narrow opening 106 of an annular T-slot 107 in the outer periphery of the top part 33 of the work-holder 31, without necessarily removing the nut 104, after which the stern part my be turned to engage oppositely arcuate, cam-like ends 108 and 109 of the plate with top and bottom walls of an enlarged inner portion 4. 110 of the T-slot. The nut 104 may then be turned against the outer face of the work-holder to hold the trip in pre determined position with a' trip extension 640 extending radially outwardly of the work-holder to be engagable with the catch 66 when the work-holder'is rotated.

Thus, the improved indexing mechanism comprising mainly the work-holding unit W and the power-output unit P, is easily installed on most popular types of drill presses of various sizes, with very little modification of such drill presses being required. Conversely, the indexing mechanism may be easily removed or disconnected to permit manual use of such drill presses in the ordinary manner.

In operation of the improved indexing mechanism shown and described, the drill fixture 39 with work 40 therein (see Figure 5) is clamped in adjusted position on rotatable work-holder 31. Motor 26 is then started to rotate the drill 22 and to drive the shaft 56 through the manual clutch 71, which in turn drives the cross-shaft 89 in clockwise direction as viewed in Figure 1. When cam 91 on this cross-shaft engages the grooved portion 92 of slide-bar 82 the latter is moved to the right to engage the clutch member 55 and drive the shaft46.

This, through link 49, rotates pinion 43 in block 44 to rotate the work-holder 31, in clockwise direction as viewed in Figure 4.

The work-holder continues to rotate until a trip 64 yieldingly moves the catch .66 from support of the springpressed detent 68. This causes two things to happen simultaneously. Firstly, the resulting spring-pressed pivotal movement of the detent causes upward movement of rod 75 and swings bell-crank 78 in counter-clockwise direction (Figure l), to move the slide-bar 82 to the left, thereby disengaging the clutch member 55 and stopping rotation of the work-holder 31. Secondly, downward swinging movement of the detent 68 moves the bifurcated inner end 70 thereof into engagement with the trip 64 which released the catch, thereby to maintain the work holder in fixed position.

While the work-holder is thus stopped, the cam 93 on the continuously rotating cross-shaft 89 will move to swing the toothed quadrant 95 upwardly, thereby rotating pinion 97, and through the gear means 18 in head 14, urging the tool-holder 17 downwardly to register drill 22 with a drill-bushing 98 in the fixture 40. The cam 93 after allowing the drill 22 to drill a hole in the work 41, allows the spring means 25 of the press to urge the toolholder back to the raised stop position shown in Figure 6.

By the time the cam 93 has permitted the tool-holder to complete its return stroke the clutch cam 91 on the other end of cross-shaft 89 will again be moving toward engagement with slidebar 82 to operate the clutch member 55 and start further rotation of the work-holder 31,,

which rotation then continues until the next succeeding trip 64 releases the detent 68 to start another drilling operation. The drilling operations are in this manner automatically performed in succession as long as there are trips on the work-holder. One such trip may be utilized through suitable switching means (not shown) to. stop the motor 26.

Thus has been provided a unitary indexing mechanism including two main units which are easily attachable to existing drill-presses of known type. It will be readily seen that with slight modifications the apparatus described may be adapted to perform operations other than drilling. Also, as an example, relatively smaller pieces of work may be applied to the work-holder 31 at a loading station at one side thereof, to have drilling or other operations performed at another station, the work-holder being automatically stopped by operation of a trip 64 on detent 68, as before.

Other modifications of the invention may be resorted to without departing from the spirit thereof or .the scope of the appended claims.

What is claimed is:

1. An automatic indexing mechanism for auxiliary attachment to a machine tool of the type including a standard having an upright, a work-supporting table, a tool-holder mounted on said standard to be movable relatively of said table, and power means mounted on said standard, said indexing mechanism comprising a workholding unit including a plate, means for releasably afiixing said plate to said table, a work-holder mounted on said plate to be rotatable about a vertical axis, a power output unit including a bracket having separable parts, means for clamping said bracket parts about said upright, a device driven by said power means for rotating said work holder on said plate, said work-holding unit including a trip on said work-holder movable in an arcuate path upon rotation of the work-holder on said plate, a member mounted on said plate, a detent on said member having a gripping portion engageable with said trip to retain said work-holder in a given fixed position on the table, a catch normally holding said detent out of the path of said trip, said trip moving in said path being engageable with said catch to release said detent toward engagement of the gripping portion with said trip, means operable on said device upon release of said detent to stop said rotation of said work-holder, and means operable upon said device while said work-holder is stopped to move said tool-holder toward and from Work on the work-holder.

2. An automatic indexing mechanism for auxiliary attachment to a machine tool of the type including a standard having an upright, a horizontal work-supporting table, a tool-holder mounted on said standard to be vertically movable relatively of said table, and power means mounted on said standard, said indexing mechanism comprising a work-holding unit including a plate, means for releasably afiixing said plate to said table, a work-holder mounted on said plate to be rotatable about a vertical axis, a power output unit including a bracket having separable parts, means for clamping said bracket parts about said upright, a device driven by said power means for rotating said work-holder on said plate, said workholding unit including trips on said work-holder movable in an arcuate path upon rotation of the Workholder on said plate, a member mounted on said plate, a detent having a gripping portion engageable with each said trip to retain said work-holder in a given fixed position of rotation on the plate, a catch normally holding said detent out of the path of said trips, said trips moving in said arcuate path being successively engageable with said catch to release said detent toward engagement of the gripping portion with the respective trip, means operable on said device upon release of said detent to stop said rotation of said Work-holder, and means operable upon said device while said work-holder is stopped to move said tool-holder toward and from work on the work-holder.

3. An automatic indexing mechanism for auxiliary attachment to a machine tool of the type including a standard having an upright, a work-supporting table mounted on said standard, a tool-holder on the standard and gear means operable to reciprocate the tool-holder vertically relatively of said table, and power means mounted on said standard, said indexing mechanism comprising a Work-holding unit, a power-output unit including a segmental bracket having mating parts and clamping means thereon for releasably attaching the segments in mating relation to the upright on a said standard, said poweroutput unit also including a shaft carried by said bracket and having means connecting said power means to drive the shaft, a shaft extension on said bracket in alignment with said shaft, a clutch between said shaft and shaft extension, cam means carried by said bracket and driven by said shaft and including a clutch-moving device for operating said clutch to drive said shaft extension, a pivoted arm carried by said bracket and having an arcuate toothed portion meshed with said gear means for reciprocating said tool-holder toward and from said table.-

and cam means carried by said bracket and driven by said shaft for reciprocating said arm to rotate said gear and thereby provide said reciprocation of the tool-holder, said work-holding unit including a plate, means for affixing said plate to the upper side of said table, a workholder mounted on said plate to rotate about a vertical axis, gear means on said plate and work-holder for rotating said work-holder about said axis, shaft means in driving connection between said shaft extension and said workholder gear means, and means being mounted on said plate for releasing said clutch upon predetermined rota tional movement of said work holder, said clutch-releasing means comprising at least one trip adjustably mounted on said work-holder to be movable in an arcuate path upon rotation thereof, a detent having a gripping portion engageable with said trip to retain said work-holder in a given fixed position of rotation on the table, a movable catch normally holding said detent out of the path of said trip, said trip moving in said arcuate path being engageable with said catch to release said detent toward engagement of the gripping portion with said trip.

4. Apparatus as set forth in claim 3, said tool-holder cam means being timed with respect to said clutch-operating cam to reciprocate the tool-holder after a said trip has operated to stop rotation of the work-holder.

5. Apparatus as set forth in claim 4, said detent being spring-pressed, said clutch-releasing means including a rigid link connected between said detent and said clutch- \movi'ng device operable by spring-pressure upon disengagement of said catch from the detent to disengage the clutch and stop rotation of the shaft extension.

6. Apparatus as set forth in claim 5, said shaft means and said rigid link each being longitudinally and angularly adjustable according to the distance between said power-output unit and said work-holding unit when mounted on a said machine tool.

References Cited in the file of this patent UNITED STATES PATENTS 673,533 Burwell May 7, 1901 804,919 Barnes Nov. 21, 1905 1,403,985 Spencer Jan. 17, 1922 

